Volcano Lab TURN THIS ONE IN
pdf
keyboard_arrow_up
School
Georgia State University *
*We aren’t endorsed by this school
Course
1121
Subject
Geology
Date
Dec 6, 2023
Type
Pages
13
Uploaded by AmbassadorDiscoveryGerbil31
Name: _______________________________ Throughout history, volcanoes have displayed enormous destructive fury and power, and they continue to do so in present times. Eruptions can change weather patterns, disrupt climate, cause widespread human suffering, and in the past, mass extinctions. Volcanoes represent complex geological systems capable of generating many dangerous phenomena. Today, about 500 million people live in regions of the world that directly subject them to volcanic risk (Auker et al., 2013). Even modest eruptions, such as the 2010 Eyjafjallajökull eruption in Iceland, have made multibillion-dollar global impacts through disruption of air traffic. The 2014 steam explosion at Mount Ontake, Japan killed 57 people without any magma reaching the surface. Although known to spew clouds of hot ash, streams of molten lava, and even generate tornadoes of fire, volcanoes can also be constructive. Volcanic ash, dust, and rocks provide important nutrients for soil, making them fertile. Volcanoes can also be harnessed for its ability to produce renewable power from natural thermal energy. It is clear that volcanic risk assessment and management are important scientific, economic, and political concerns, especially in densely populated areas. To evaluate and manage volcanic risks in our lives, we first must learn and understand the basic characteristics of volcanoes. In this lab, you will be describing and identifying common volcano types, relating volcano styles with tectonic settings, geographic location, and potential volcanic hazards.
Part 1: Review Some common misconceptions
about volcanoes:
By the end of this lab, you will have achieved these learning goals
:
▪
All volcanoes have tall peaks and large craters at the summit. ▪
Volcanoes only occur in warm areas. ▪
Volcanoes are randomly located across the earth’s surface. ▪
There is no pattern to volcano formation. ▪
Volcanoes are only found on land. ▪
Volcanoes only erupt straight up through the top vent. ▪
All volcanoes erupt violently.
▪
Discuss the major types of volcanic landforms, how they are formed and modified, and typical physical characteristics. ▪
Be able to explain what determines the shape, size, slope, and level of explosivity of a volcano. ▪
Understand the type of tectonic boundaries and geographic settings that produce certain types of volcanoes. ▪
List types of geologic hazards associated with different types of volcanic eruptions. ▪
Name at least three famous volcanoes.
Deliverables ▪
Word document ▪
Excel sheet (for Part 2, question 8)
Lab Outline ▪
Part 1: Review ▪
Part 2: Google Earth tour ▪
Excel sheet (for Part 2, question 8) Additional Resources ▪
“How to Navigate GE Tours” guide Volcano Lab Activity Types of volcanoes, tectonic settings, and hazards
A satellite image of New Zealand's White Island on Dec. 11, 2019, three days after the volcano erupted. (Image credit: Satellite image ©2019 Maxar Technologies)
It is highly recommended
that you review the Google Earth tutorial video and written guide under Additional Resources
on iCollege before starting the lab assignment.
Begin the Volcanos Lab Google Earth tour
!
Make sure you are in mode and remain so for the entire tour. Answer the following questions. Short videos available in the right-hand information box on Slide 2
and will help you to answer this first part. You will not be using the map until Part 2.
(My answers are highlighted and italicized to provide clear placement! Also to make it easier to read!!) 1.
Watch Video 1 and explain in your own words why volcanism occurs in subduction zones. When continental and oceanic crust clash, a subduction volcano occurs. The oceanic crust melts and migrates higher, resulting in a volcano erupting on the surface. The oceanic plate is moving beneath the continental plate. Subduction happens when one plate has more water and is consequently denser than the other. Trenches are produced as a result. Volcanoes develop when moist rock is compressed, causing water to escape and the Earth's mantle to partially melt. Subduction zones, or convergent plate boundaries, where an oceanic plate slips beneath a continental plate and contributes to the ascent of magma to the surface, are where stratovolcanoes tend to occur. At strike-slip zones, where two plates move laterally past one other, volcanoes are uncommon. 2.
Watch Video 1 and explain in your own words the mechanism that creates volcanoes at “hot spots” and rifts. When there are rifts, the magma rises in between the gaps and forms volcanoes. This keeps on the earth's mantle in hot regions, and the melting of rocks (magma) makes its way through the fissures in the earth's crust. A hot spot is a place deep inside the Earth's mantle where heat rises through the convection process. The melting of rock is aided by this heat. Volcanoes are formed when melted rock, known as magma, pushes through fractures in the crust. Magma rises into the breach between divergent plates, forming rift volcanoes. As a result, they occur at or near plate borders.
3.
Watch Video 2 and determine why some volcanoes have a shield/dome shape while some have a cone shape. Shield
volcanoes are not steep, they may be very large. Shield volcanoes are common at spreading centers or intraplate hot spots
Cones
grow rapidly, usually from a single eruption cycle.
4.
Watch Video 3 and state the reasons for why some volcanoes experience effusive (gentle) eruptions and why some experience explosive eruptions? The viscosity and gas content of magma determine the eruption of volcanoes. Basalt, which has a low viscosity and gas content, is ejected by several Hawaiian volcanoes. There is a lot of gas there, and the magma doesn't build up much pressure. Rhyolite magmas, on the other hand, are viscous and may store a significant amount of gas. When the magma moves into the vent and the pressure drops, the gas tries to escape. Because the magma is so sticky, the gas bubbles are unable to grow. The lava is blasted into ash-sized bits and forced released into the atmosphere when enough bubbles develop.
5.
Watch Video 4 and determine the most dangerous hazards associated with volcanoes. Provide a brief explanation. The most dangerous hazards associated with volcanoes are tephra, lahars, and pyroclastic flows. Tephra, rock fragments and particles ejected from a volcano, can be flung at extreme distances. It consists of big rocks, lava bombs, and ash that can destroy cars, planes, roads, etc. Tephra that remains can turn into lahars that mix with streams of water, rainfall, or melting glacial ice to create mudflows. Lahars are so powerful that they can tear down trees, bridges, and buildings. It also travels fast, it is unable to outrun, resulting in many casualties. Pyroclastic flows are hot, dense clouds of toxic gases mixed with tephra. They roll down the flanks of volcanoes at a great speed, and everything in their way is completely obliterated.
2
GEOL 1121K Volcano Lab Activity
3
GEOL 1121K Volcano Lab Activity
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help
Part 2: Google Earth tour Volcano shape is strongly controlled by eruptive style, which in turn is controlled by magma composition and tectonic setting. This part of the lab is intended to give you the opportunity to virtually examine volcanoes from around the globe through 3-D satellite imagery, and to interpret the tectonic settings in which they form. Use the Google Earth tour link provided below to answer the following questions. It is highly recommended
that you review the Google Earth tutorial video and written guide under Additional Resources
on iCollege before starting the lab assignment. For this lab, all locations have been programmed in the slides for you. You will not need to click on any place markers or use the “Search” function. Just move through the slides using the slide arrow buttons, and you will be flown to the volcano location. Use your mouse and keyboard to move/look around. Your map view is set to 3D, and you will not need to toggle to 2D at any point. Remain in “Present” mode unless noted otherwise.
Use the Volcanos Lab Google Earth tour
! CLICK . 1.
Navigate to Slide 4
: Chile, in South America
. Look for the green placemark and zoom to Chile’s capital, Santiago, at an eye altitude of ~1000 km. You can find altitude values at the bottom right corner of the Status Bar. Make sure that north (the red tip) is pointing towards the top. Stay on this slide and tilt
the viewing angle so that you can look northward along the South American coast. Briefly describe the major tectonic features and landforms that you see. 2.
Now, you will be researching three
types of famous volcanoes (out of the six volcanoes provided below) using this Volcanoes GE tour and online resources. You must select one volcano from each
column below. Once you have picked your choice of volcanoes, find the appropriate question section for your selected volcanoes in the next few pages, and answer all questions. Volcano Type “A”
Volcano Type “B”
Volcano Type “C”
Aniakchak, Alaska
Descabezado Grande, Chile
Alayta, Ethiopia
Mount Saint Helens, Washington
Mount Fuji, Japan
Mauna Loa, Hawaii
4
GEOL 1121K Volcano Lab Activity
Descabezado
Grande
of central Chile
Navigate to Slide 5 a)
Use your cursor, and the ruler tool when needed, to find the size and shape of the volcano by filling in the spaces, below. You will need to exit out of “Present” mode to use the ruler (press ESC or click the back button at the upper left corner). To find elevation values, you can point your cursor on specific parts of the volcano in the map and read the elevation values (seen in bottom right corner of the status bar, it is the unit value to the RIGHT of the coordinates. If it does not pop up, you need to zoom in a little more); you can also use the provided elevation profile image (in the photo gallery) to obtain some of these values. Note that these values are approximate and should be generally close to actual values reported by online resources. Record YOUR approximations: •
Maximum height (elevation) of the volcano above sea level: ______3500__________
meters •
Base elevation of the volcano: __
____3953
__________ meters •
Relief (maximum elevation – base elevation) = ________453________
meters total height •
Base width: ______1150________
meters. •
Average slope of volcano ((relief ÷ ½
width)*100%): __79_____
% b)
Describe
the overall shape
of Descabezado. It is known for its “headless” flat topped look and is described as cone shaped. It is steep and bumpy all around the volcano Then, fill out this table based on your observations from Google Earth and from online research. You may refer to the tables under Additional Resources
for some help. c)
What type of volcano is this, based on size, shape, and composition? stratovolcano
d)
Describe the major geologic hazards in the surrounding region associated with this volcano. Several hazards may affect the area around the volcano, such as lava flows, pyroclastic flows, lahars, and landslides or debris avalanches.
e)
Zoom out and examine the region. Describe the likely tectonic setting of the volcanoes of the Andes mountains (crust types and relative motion). Hint: is there a deep ocean trench to the west of the mountains? The volcanoes near Andes mountains formed due to subduction of one oceanic plate under another continental crust which give rise to those volcanoes due to melting of the crust. As one oceanic crust is subducting beneath another continental crust so this boundary is a Convergent Oceanic-Continent Boundary.
f)
When was the last eruption? Is this volcano considered active, dormant, or extinct? (
Slide 3 may be helpful) Magma Composition
Rock Type
Flow Rate
Silica Content
Viscosity
Explosiveness
Felsic
Tuff
Low
High
High
Very Explosive
5
GEOL 1121K Volcano Lab Activity
The last eruption was on 1933. So it comes under the dormant volcano category.
6
GEOL 1121K Volcano Lab Activity
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help
Mt. St. Helens in southern Washington, USA
Navigate to Slide 6
a)
Use your cursor, and the ruler tool when needed, to find the size and shape of the volcano by filling in the spaces, below. You will need to exit out of “Present” mode to use the ruler (press ESC or click the back button at the upper left corner). To find elevation values, you can point your cursor on specific parts of the volcano in the map and read the elevation values (seen in bottom right corner of the status bar, it is the unit value to the RIGHT of the coordinates. If it does not pop up, you need to zoom in a little more); you can also use the provided elevation profile image (in the photo gallery) to obtain some of these values. Note that these values are approximate and should be generally close to actual values reported by online resources. Record YOUR approximations: •
Maximum height (elevation) of the volcano above sea level: _____2350___________ meters •
Base elevation of the volcano: ________1416________ meters •
Relief (maximum elevation – base elevation) = _________1114_______ meters total height •
Base width: ____5709____________ meters. •
Average slope of volcano ((relief ÷ ½
width)*100%): _____39__ % b)
Describe
the overall shape
of Mt. St. Helens: A comical shape, it is like a wrap around with an opening. Symmetrical cone Then, fill out this table based on your observations from Google Earth and from online research. You may refer to the tables under Additional Resources
for some help. c)
What type of volcano is this, based on size, shape, and composition? Stratovolcano d)
Describe the major geologic hazards in the surrounding region associated with this volcano. This Volcano is very eruptive, and the viscosity is very low e)
Zoom out and examine the region. Are there any other volcanoes nearby? Describe the likely tectonic setting
of the volcanoes of the Cascade Range. Support your answer with observations on the major tectonic landforms of the region. There are no other volcanos nearby, it is surrounded by green plains and has a Juan De Luca for tectonic plate f)
When was the last eruption? Is this volcano considered active, dormant, or extinct? (
Slide 3 may be helpful) July 10, 2008, it is still active Magma Composition
Rock Type
Flow Rate
Silica Content
Viscosity
Explosiveness
Mafic
Basalt
High
Low
Low
Non Explosive
7
GEOL 1121K Volcano Lab Activity
Mauna Loa on the island of Hawaii (central Pacific Ocean) Navigate to Slide 7
a)
Use your cursor, and the ruler tool when needed, to find the size and shape of the volcano by filling in the spaces, below. You will need to exit out of “Present” mode to use the ruler (press ESC or click the back button at the upper left corner). To find elevation values, you can point your cursor on specific parts of the volcano in the map and read the elevation values (seen in bottom right corner of the status bar, it is the unit value to the RIGHT of the coordinates. If it does not pop up, you need to zoom in a little more); you can also use the provided elevation profile image (in the photo gallery) to obtain some of these values. Note that these values are approximate and should be generally close to actual values reported by online resources. Record YOUR approximations: •
Maximum height (elevation) of the volcano above sea level: ______4120__________ meters •
Base elevation of the volcano: _______3030_________ meters •
Relief (maximum elevation – base elevation) = ______1090__________ meters total height •
Base width: ____10230____________ meters. •
Average slope of volcano ((relief ÷ ½
width)*100%): ____21.3___ % b)
Describe the overall shape
of Mt. St. Helens: It is not steep and it looks like diverging planes Then, fill out this table based on your observations from Google Earth and from online research. You may refer to the tables under Additional Resources
for some help. c)
What type of volcano is this, based on size, shape, and composition? Shield Volcano d)
Describe the major geologic hazards in the surrounding region associated with this volcano. There are little e)
Zoom out and examine the region. Describe the likely tectonic setting of the Hawaiian Islands. Support your answer with observations on the major tectonic landforms of the region. It is very flat due to the tectonic plating being ocean continental convergent
f)
When was the last eruption? Is this volcano considered active, dormant, or extinct? (
Slide 3 may be helpful) April 15, 1984, It is still very active Magma Composition
Rock Type
Flow Rate
Silica Content
Viscosity
Explosiveness
Mafic
Basalt
High
Low
Low
Non explosive
8
GEOL 1121K Volcano Lab Activity
Mt. Fuji, Japan Navigate to Slide 8
a)
Use your cursor, and the ruler tool when needed, to find the size and shape of the volcano by filling in the spaces, below. You will need to exit out of “Present” mode to use the ruler (press ESC or click the back button at the upper left corner). To find elevation values, you can point your cursor on specific parts of the volcano in the map and read the elevation values (seen in bottom right corner of the status bar, it is the unit value to the RIGHT of the coordinates. If it does not pop up, you need to zoom in a little more); you can also use the provided elevation profile image (in the photo gallery) to obtain some of these values. Note that these values are approximate and should be generally close to actual values reported by online resources. Record YOUR approximations: •
Maximum height (elevation) of the volcano above sea level: _______3730_________ meters •
Base elevation of the volcano: __________1480______ meters •
Relief (maximum elevation – base elevation) = ________2250________ meters total height •
Base width: _____8935___________ meters. •
Average slope of volcano ((relief ÷ ½
width)*100%): ___50.4____ % b)
Describe the overall shape
of Mt. Fuji: It is very steep with flat surroundings Then, fill out this table based on your observations from Google Earth and from online research. You may refer to the tables under Additional Resources
for some help. c)
What type of volcano is this, based on size, shape, and composition? Strato Volcano d)
Describe the major geologic hazards associated with this volcano. It has been inactive for more than 3 centuries, but when the time comes it will be extremely violent e)
Zoom out and examine the region. Describe the likely tectonic setting of the volcanoes in Japanese region. Support your answer with observations on the major tectonic landforms of the region. It is surrounded by continental since the plate tectonic landform is continental convergent boundary
f)
When was the last eruption? Is this volcano considered active, dormant, or extinct? (
Slide 3 may be helpful) December 16, 1707, It is still active Magma Composition
Rock Type
Flow Rate
Silica Content
Viscosity
Explosiveness
Mafic
Basalt
High
Low
Low
Non explosive
9
GEOL 1121K Volcano Lab Activity
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help
Mt. Alayta, Ethiopia Navigate to Slide 9
a)
Use your cursor, and the ruler tool when needed, to find the size and shape of the volcano by filling in the spaces, below. You will need to exit out of “Present” mode to use the ruler (press ESC or click the back button at the upper left corner). To find elevation values, you can point your cursor on specific parts of the volcano in the map and read the elevation values (seen in bottom right corner of the status bar, it is the unit value to the RIGHT of the coordinates. If it does not pop up, you need to zoom in a little more); you can also use the provided elevation profile image (in the photo gallery) to obtain some of these values. Note that these values are approximate and should be generally close to actual values reported by online resources. Record YOUR approximations: •
Maximum height (elevation) of the volcano above sea level: _______1500_________ meters •
Base elevation of the volcano: _______1380_________ meters •
Relief (maximum elevation – base elevation) = _______120_________ meters total height •
Base width: ______560__________ meters. •
Average slope of volcano ((relief ÷ ½
width)*100%): ___52____ % b)
Describe the overall shape of Mt. Alayta: Very flat and not very steep Then, fill out this table based on your observations from Google Earth and from online research. You may refer to the tables under Additional Resources
for some help. c)
What type of volcano is this, based on size, shape, and composition? Shield Volcano d)
Describe the major geologic hazards in the surrounding region associated with this volcano. Not many as it is an inactive volcano e)
Zoom out and examine the region. Describe the likely tectonic setting of the volcanoes in the region (crust type and motion). Support your answer with observations on the major tectonic landforms of the region. Very flat volcano with small elevation
f)
When was the last eruption? Is this volcano considered active, dormant, or extinct? (
Slide 3 may be helpful) 1915, It Is inactive
Magma Composition
Rock Type
Flow Rate
Silica Content
Viscosity
Explosiveness
Mafic
Basalt
High
Low
Low
Non Explosive
10
GEOL 1121K Volcano Lab Activity
Mt Aniakchak, Alaska Navigate to Slide 10
a)
Use your cursor, and the ruler tool when needed, to find the size and shape of the volcano by filling in the spaces, below. You will need to exit out of “Present” mode to use the ruler (press ESC or click the back button at the upper left corner). To find elevation values, you can point your cursor on specific parts of the volcano in the map and read the elevation values (seen in bottom right corner of the status bar, it is the unit value to the RIGHT of the coordinates. If it does not pop up, you need to zoom in a little more); you can also use the provided elevation profile image (in the photo gallery) to obtain some of these values. Note that these values are approximate and should be generally close to actual values reported by online resources. Record YOUR approximations: •
Maximum height (elevation) of the volcano above sea level: ________934________ meters •
Base elevation of the volcano: ________634________ meters •
Relief (maximum elevation – base elevation) = ________300________ meters total height •
Base width: ________2024________ meters. •
Average slope of volcano ((relief ÷ ½
width)*100%): ___30____ % b)
Describe
the overall shape
of Aniakchak: It is Circular and is not symmetrical Then, fill out this table based on your observations from Google Earth and from online research. You may refer to the tables under Additional Resources
for some help. c)
What type of volcano is this, based on size, shape, and composition? Caldera Volcano d)
Describe the major geologic hazards in the surrounding region associated with this volcano. Lots of ash due to its high explositivity Lots of rock fragments e)
Zoom out and examine the region. Describe the likely tectonic setting of the volcanoes in the region (crust type and motion). Support your answer with observations on the major tectonic landforms of the region. It is surrounded by another crater f)
When was the last eruption? Is this volcano considered active, dormant, or extinct? (
Slide 3 may be helpful) 1931, It is still active Magma Composition
Rock Type
Flow Rate
Silica Content
Viscosity
Explosiveness
Felsic
Tuff
Low
High
High
Very Explosive
11
GEOL 1121K Volcano Lab Activity
Plot your measured values onto the separate Excel sheet provided. For width, convert your values from meters to kilometers. For composition, convert the names to numbers (Mafic = 1, Intermediate = 2, Felsic = 3). The four graphs will automatically fill in when the table is complete. This will be your second deliverable. --------------------------------------------------------------------------------------------------------- Summarize volcano type/composition relationships.
3.
Go back to your answers for each volcano examined. Use your observations, Excel chart results, and interpretations to complete the following statements. Use the tables under Additional Resources
for appropriate terms. ➢
Shield
volcanoes usually have a _______wide dome______ shape, ___low______ slope, and a __________mafic___ composition. The magma has a _____high___volume flow rate with ______low_____ viscosity. It likely has ____low______ silica content. Shield volcanoes typically erupt with ___non_______ explosivity. The most common hazard(s) are _____possible sudden violent reactions of gas and debris___________. The most common rock type(s) formed here is/are ________Basalt_________. Shield volcanoes commonly form in these tectonic settings: _____Divergent plate boundaries___________. ➢
Composite
volcanoes usually have a _______steep cone______ shape, _____steep____ slope, and a ________felsic_____ composition. The magma has a _____low___volume flow rate with ______high_____ viscosity. It likely has _____high_____ silica content. Compositive volcanoes typically erupt with _____very_high____ explosivity. The most common hazard(s) are ________proclaystic flow of ash and fall________. The most common rock type(s) formed here are ________tuff_________. The most common tectonic setting of composite volcanoes is/are at __________convergent______ boundaries. ➢
Caldera volcanoes usually have a _____open crater with raised rim________ shape, ___Moderate______ slope, and a ______felsic_______ composition. The magma has a ___low_____volume flow rate with ____high_______ viscosity. It likely has ___high_______ silica content. Caldera volcanoes typically erupt with __very_______ explosivity. The most common hazard(s) are ______violent explosions, rock debris, ash, and toxic gas__________. The most common rock type(s) formed here are ______tuff___________. Caldera volcanoes commonly form in these tectonic settings: intercontinental extension__________. 12
GEOL 1121K Volcano Lab Activity
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help
13
GEOL 1121K Volcano Lab Activity